A ward in our stake is celebrating their 100th anniversary, and one of the organizers for the celebration asked me if there was any way to go back in MLS (as far as it can go) and find past auxiliaries.

Once Bishops, RS presidents, and other callings are replaced, can they be recovered for historical purposes?

MLS does not keep any historical calling data. CDOL is the only place I know of that will have limited historical data of major callings for a unit, but only those in key leadership positions can access it.

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